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The iPhone 4 Solar Charger

I haven't had any problems with the iPhone 4 battery so far (I managed to make it last 38 hours once), but in case you were wondering if there was a way to use solar power to get more battery life - well, here it is.

The Frostfire Mooncharge Hybrid Solar Battery Case For iPhone 4 gives your device 5 extra minutes of calling or 50 minutes of stand-by mode with 20 minutes of direct sunlight, but if you charge the battery inside the case via USB you get 5 additional hours of calling. So, not really powerful when it comes to solar charging - not unless you leave the phone in direct sunlight for a couple of hours.

Federico is the founder and editor-in-chief of MacStories, where he writes about Apple with a focus on apps, developers, and mobile software. He can also be found in the iBooks Store and on his two podcasts, Connected and Virtual.